With the popularization of broadband, a variety of servers has been provided with the use of web systems. The construction of a web system can be provided by all of companies because of a price reduction in hardware, web server systems, and package products for service construction. The web application provides not only conventional static screens, but also dynamic screens with the use of a dynamic HTML (hypertext markup language) technique or an Ajax (asynchronous JavaScript+extensible markup language (XML)) technique to improve usability, thus advancing to a trend of differentiation.
On the other hand, distinctive adverse effects of online service arise. When a service is provided face-to-face, how to deal with a client can be changed according to a response of the client. However, in the case of online service, it is difficult to look directly at a face of the client, thereby making it difficult to grasp the response of the client. For that reason, it is difficult to provide a detailed service according to the response of the client.
On the contrary, a technique is disclosed in which the operation of a mouse or a keyboard by the user on the web browser is recorded to grasp a usage status of the service (Patent Literature 3). In the technique of Patent Literature 3, the operation of the mouse and the keyboard of the user on the web browser is recorded, and a script program to be sent to a server is inserted into a response of the web application. In this case, the response represents data for screen creation of the web application, and is described by an HTML language or the like. The inserted script program is deciphered and executed by a script execution engine of the web browser, traps the operation of the mouse and the keyboard by the user on the browser, and records the captured operation as an operation log. A service provider collects and analyzes an operation log so as to grasp where the user has clicked a web page, and where the user has read the web page. Thus, the service provider can investigate a response of the client to the online service, and establish an improvement.
As other related arts, several techniques for capturing a screen of the web application, that is, information from an HTML have been disclosed. As a method of representing a area of a document described in a markup language such as the HTML is, an XPath (XML Path Language) disclosed in Nonpatent Literature 2 has been widely used. There has been widely used a method of representing the area with the use of the XPath, and capturing information from the screen of the web application with the use of an execution engine of the XPath. Also, a method of defining an information extraction rule, and extracting information, by focusing on a table and a list structure of the HTML has been disclosed in Patent Literature 1. Further, a technique in which a script code for recording processing within a client is inserted into a response from the web server in advance to save the record of the processing of the client has been disclosed in Patent Literature 2. A technique of grasping the usage status of the service disclosed above is frequently provided in the configuration of an SaaS (software as a service) or by the existing application in the form of add-on.